Loading and unloading crane



July 25, 1961 M. SMITH LOADING AND UNLOADING CRANE 2 Sheets-Sheet 1Filed June 14, 1957 INVENTOR ATTORNEY MAX 1.. SMITH July 25, 1961 M. L.SMITH 2,993,605

LOADING AND UNLOADING CRANE Filed June 14, 1957 2 Sheets-Sheet 2 5 I LINVENTOR F7615 MAX L. SMITH ATTORNEY United States Patent Ofifiee2,993,605 Patented July 25, 1961 2,993,605 LOADING AND UNLOADING CRANEMax L. Smith, Fort Pierce, Fla., assignor, by mesne assignments, toCurtiss-Wright Corporation, South Bend, Ind, a corporation of DelawareFiled June 14, 1957, Ser. No. 665,704 2 Claims. (Cl. 212-55) The presentinvention relates broadly to cranes for loading and unloading ofmaterials, and more specifically to a crane of the travelling boom typeadapted for mounting on the bed of a truck or the like.

An object of the present invention is to provide a crane or boomstructure of novel and simple construction adapted to be mounted upon atruck platform and which can be easily extended or retracted, androtated in a circle to the proper angle.

Another object of the present invention is to provide a crane employingthe principle of a traveling boom having the point of lift always at theend of the boom, and wherein the lifting force is supplied by ahydraulic cylinder or the like located in the boom and transmitted to alifting hook by a conventional roller chain.

Another object of the present invention is to provide a crane of anature wherein the whole boom travels as a unit, horizontally withrespect to a vertical mount or support for the crane.

A still further object of the present invention is to provide in such acrane, mounting means adapted for providing a rotating movement to thecrane by use of a single interior piece of 'metal tubing rotatablysupported within an exterior piece of tubing.

A further object of the present invention is to provide a crane havinghydraulic motors and worm gear reduces associated with a verticalsupport for the boom, whereby the boom as a unit may be rotated to adesired angular disposition with respect to a truck bed or the like.

Another object of the invention is to provide a novel mounting for theboom whereby it can be swung around in a complete circle, andadditionally means for raising and lowering a 'hoist carried by a boomand wherein the construction and operation are simple and sturdy indesign as also inexpensive to manufacture and operate.

A still further object of the present invention is to provide a craneadapted for mounting on a truck bed utilizing a wholly movable boom inwhich the operating mechanism for a chain lift is secured in a positionto prevent external disturbances.

Other objects and advantages of the invention will be more readilyapparent from the following detailed description of an embodimentthereof when taken together with the accompanying drawings in which:

FIGURE 1 is a side elevational view of the crane of the presentinvention, parts being broken away for clarity;

FIGURE 2 is a top plan view of the device of FIG- URE 1;

FIGURE 3 is a rear end elevational view of the crane;

FIGURE 4 is a fragmentary sectional view taken on the line 44 of FIGURE1; and

FIGURE 5 is a fragmentary sectional view taken on the line 55 of FIGURE4.

Referring to the drawings in detail, the device of the present inventionis shown applied to a motor vehicle truck bed mounted on a truck frame12. A tubular vertical support 14 having a lower flange 16 is mounted onthe truck bed 10 by means of bolts or the like 18. Angularly disposedbracing supports 20 have their lower ends secured to the truck bed bymeans of bolts 22 and the upper ends of the braces are secured to thetubular vertical support 14 as by welding or the like. An upper flange24 is provided at the top of the tubular vertical support 14 and aflixedthereto by welding such as at 26 on the exterior and at 28 on theinterior. This upper flange 24 serves as a support for the boom androtating structure of the crane as will appear hereinafter.

An inner tubular vertical support 30 is inserted in and extends throughtubular vertical support 14, as shown in FIGURES 1 and 5, and has at itsupper end a flange 32 welded thereto at 34. This flange 32 rides on andis supported by the upper flange 24 on the tubular vertical support 14and is rotatable thereon. The lower end of the inner tubular verticalsupport 30 extends below the support 14 and has secured thereto a gear36 which, by means of a chain 38, is associated with a sprocket gear 40carried on a shaft of reducing gear 42 for providing rotational movementto the inner vertical support 30 by means of oil motor 44 connected intothe reducing gear by shaft 46. By means of a plurality of oil inlets andoutlets of a known type and disposition, diagrammatically indicated at48, the oil motor 44 can be so operated as to rotate the inner tubularvertical support 30 in any desired direction of rotation.

Affixed to and carried by the flange 32 of the inner tubular verticalsupport 30 is a boom head 50. Upper and lower sets of rollers 52 and 54respectively, are rotatably mounted in the boom head 50, as shown indetail in FIGURE 4, by means of shafts 56 extending through the sidewalls of the boom head 50. Washers or collars 58 are operativelyassociated with the rollers 52 and 54 and constitute guide means for thetraveling boom, generally designated 60, which is mounted for movementbetween the upper and lower sets of rollers and for rolling engagementtherewith into extended or retracted position.

The boom 60 is of substantially box-like configuration having sidemembers 62 and upper and lower inturned flanges 64 and 66 respectivelyadapted to ride in rolling engagement with and be supported betweenupper and lower rollers 52. and 54. Mounted interiorly of boom .60 is ahydraulic cylinder, diagrammatically shown at 68, and secured to theboom structure at 70. ,A shaft 72 is secured to the piston of thehydraulic cylinder 68 and is telescopically mounted with respectthereto, as indicated by the arrow 74 in FIGURE 1. At its free outerend, the shaft 72 carries a rotatably mounted gear wheel 76. A chain 78is secured at 80 to the boom 60 and extends around gear wheel 76,through a chain guide 82 over another gear wheel 84 in proximity to thefree end of the boom 60, and at its lower vertically extended end isadapted to support a lifting hook 86 or the like, although manifestlyany desired lifting or carrying means can be supported by the chain.

The chain 78 constitutes a lift chain actuatable by means of thehydraulic cylinder 68 through hydraulic leads 88 and 90 attached intoopposite ends of the cylinder 68 and extending to a suitable hydraulicpressure means or source whereby the piston in the cylinder 68 canoperate to drive shaft 72 into retracted or extended position andthereby, by means of gear wheel 76 acting on chain 78, serve to raise orlower the lifting hook 86 as desired. A spring 92, supported from theboom head 50, serves as a resilient support for the hydraulic lines toaccommodate the lines to horizontal traveling of the boom 60. As will beunderstood hereinafter, the actuation of the lift hook and chainapparatus is wholly independent of operational movement of the boomeither in horizontal extension or in rotation.

Atrixed to the boom 60, interiorly thereof, is a second chain 94 securedat 96 which passes over a gear wheel 98, under gear wheel 100, over gearwheel 102, and is again secured to boom 60 at 104. An oil motor 106 ismounted on boom head 50 and connected into a reduction gear 108 by meansof shaft 110. A stub gear 112 is to retracted position. A rear stop 118and a front stop 128 are provided on the exterior of boom 60 to limitthe extent of movement thereof by coaction with boom head 50 in anobvious manner.

Springs 122 interconnect the boom with the boom head by means of arm 124to facilitate return of the boom 60 from a fully retracted position toan extended position.

From the foregoing description, it is believed that operation of thepresent device will be readily apparent.

The boom can be extended or retracted by means of the chain 94; thelifting hook can be actuated in the directions of the arrow in FIGURE 1by means of chain 78 and associated mechanism; and the boom 60 can beangularly rotated by means of the chain 38 and associated mechanism.Each of these operations is separate and distinct from each of the otheroperations, which provides a very facile operation to the device of thisinvention.

Manifestly, minor changes in details of construction can be made in thepresent invention without departing from the spirit and scope thereof asdefined in, and limited solely by, the appended claims.

I claim: 1. A boom crane, comprising: a vertically disposed tubularsupport having an inner support member rotatably disposed therein andsupported on the upper end thereof, a boom head 'fixed to said innersupport and rotatable therewith on said tubular support, said boom headincluding side wall members having spaced upper and lower roller meanssecured therebetween and serving as cross braces for said side Walls, areciprocal boom disposed through said boom head and between said upperand lower roller means for cantilevered support thereby in extendedpositions thereof, said boom comprising parallel spaced channel beammembers in open faced relation and having the flanges thereof in rollingengagement with said roller means, a drive chain provided on theunderside of said boom between the ends thereof and within theprotection of the spaced lower flanges of the channel beams thereof,chain drive means mounted on said boom head and operatively engaged tosaid drive chain for reciprocating said boom relative to said boom head,drive means operatively engaged to the lower end of said inner supportmember for rotation thereof and of said boom head and boom therewith, alift chain mounted within said boom and extending beyond one endthereof, a power cylinder mounted within the other end of said boom andoperatively engaged to said lift chain within a reversely laid loopthereof, and means operatively connected between said boom and boom headfor assistance in the extension of said boom for loading and unloadingoperations.

2. A boom crane, comprising: a vertically disposed tubular supporthaving an inner support member rotatably disposed therein and supportedon the upper end thereof, a boom head fixed to said inner support androtatable therewith on said tubular support, said boom head includingside wall members having spaced upper and lower roller means securedtherebetween and serving as cross braces for said side walls areciprocal boom disposed through said boom head =and between said upperand lower roller means for cantilevered support thereby in extendedpositions thereof, said boom comprising parallel spaced channel beammembers in open faced relation and having the flanges thereof in rollingengagement with said roller means, a drive chain provided on theunderside of said boom between the ends thereof and Within theprotection of the spaced lower flanges of the channel beams thereof,chain drive means mounted on said boom head and operatively engaged tosaid drive chain for reciprocating said boom relative to said boom head,drive means operatively engaged to the lower end of said inner supportmember, for rotation thereof and of said boom head and boom therewith, alift chain mounted within said boom and extending beyond one endthereof, and a power cylinder mounted within the other end of said boomand operatively engaged to said lift chain within a reversely laid loopthereof.

References Cited in the file of this patent- UNITED STATES PATENTS678,188 Macbeth July 9, 1901 2,382,299 Deiters 'Aug. 14, 1945 2,462,926Wilson Mar. 1, 1949 2,528,588 Forslund Nov. 7, 1950 2,592,993 Adams Apr.15, 1952 2,755,939 Rush July 24, 1956 2,787,383 Antos Apr. 2, 19572,792,138 Olson May 14, 1957

